STRUCT SCMI_INFO(9)

📦 version 7.3.1, in nixpkgs unstable

💖 NAME 💖

struct scmi_info — the structure that represents one SCMI instance, bestie. It's the main character of an SCMI instance, fr fr.

✨ SYNOPSIS ✨

okay so here's the whole shape of it, no cap, copy it exactly:

struct scmi_info {
    int id;
    struct device *dev;
    const struct scmi_desc *desc;
    struct scmi_base_info version;
    struct scmi_handle handle;
    struct scmi_xfers_info tx_minfo;
    struct scmi_xfers_info rx_minfo;
    struct idr tx_idr;
    struct idr rx_idr;
    struct idr protocols;
    struct mutex protocols_mtx;
    u8 *protocols_imp;
    struct idr active_protocols;
    void *notify_priv;
    struct list_head node;
    int users;
    struct notifier_block bus_nb;
    struct notifier_block dev_req_nb;
    struct mutex devreq_mtx;
    struct scmi_debug_info *dbg;
    void *raw;
 };

🎀 Members 🎀

like, every single field, explained with love 💅

  • id — a sequence number starting from zero that identifies this instance 🫶
  • dev — device pointer, classic
  • desc — the SoC description for this instance
  • version — SCMI revision info: it's giving protocol version, implementation version, and (sub-)vendor identification all in one ✨
  • handle — the actual instance of the SCMI handle you send out to clients
  • tx_minfo — Universal Transmit Message management info
  • rx_minfo — Universal Receive Message management info (yes the receive twin, they're a matching set 🎀)
  • tx_idr — IDR object mapping a protocol id to the Tx channel info pointer
  • rx_idr — IDR object mapping a protocol id to the Rx channel info pointer
  • protocols — IDR for the protocols' instance descriptors initialized for this SCMI instance; it gets populated on the protocol's first attempted usage 👑
  • protocols_mtx — a mutex protecting protocols instances initialization, keeping it safe 🫶
  • protocols_imp — list of protocols implemented, currently a maximum of scmi_base_info.num_protocols elements allocated by the base protocol
  • active_protocols — IDR storing device_nodes for protocols actually defined in the DT and confirmed as implemented by fw. iykyk
  • notify_priv — pointer to a private data structure specific to notifications 🙈
  • node — list head
  • users — number of users of this instance
  • bus_nb — a notifier listening for device bind/unbind on the scmi bus
  • dev_req_nb — a notifier listening for device request/unrequest on the scmi bus
  • devreq_mtx — a mutex that serializes device creation for this SCMI instance
  • dbg — pointer to debugfs related data (if any)
  • raw — an opaque reference handle used by SCMI Raw mode 🔥

🌈 SEE ALSO 🌈

Kernel file ./drivers/firmware/arm_scmi/driver.c, plus the whole friend group 😭💖:

okay that's the whole thing, you ate that 💅 this page lives in ./drivers/firmware/arm_scmi, it's the Kernel API Manual, and the version/date stamp on it is October 2026 — iconic, see you in the next one bestie 🦋💜

📦 where this page comes from